PDA

View Full Version : Ultra sonic leak detection



clivet
28-11-2006, 04:51 PM
I'm almost regretting this before i start! has anyone seen,used, touched, played with any ultra sonic leak detection gear, we are thinking of investing in the equipment but i dont want to commit funds on the say so of a hot shot salesman.

A suited gent who works for a mighty intrenational fridge company tells me they are the best thing ever but due to a "technical problem" he was unable to prove it. Any views:confused:

Brian_UK
28-11-2006, 08:16 PM
They are supposed to be the 'bees knees', they are used (or used to be used) by car manufacturers to find leaks in completed car bodies etc.

Used to use just the listening device without the sound source being used. Found it good at finding leaks due to the sound escaping gas makes.

LRAC
28-11-2006, 08:18 PM
Hi Clivet and thanks for your PM

We trialed these devices and yes they are good, but there is a big down side to it.

For these devices to work it must be completly silent in the area you are working in, take for example even somebody using a sweeping brush can **** the whole thing up let alone normal refrigeration plant running.( the salesman shouted into the test unit and nothing registered but thats not real life).

We kept 1 just for the workshop when we build custom built condensing units or packs(totally silent area for pressure testing).

They are not ideal for engineers use in the field, too much background interference.May be worth keeping 1 just for those one off jobs?

If i remember correctly they are more tuned to detecting sounds at 40Khz if your gas leak is on this frequency ok, but if not your stuufed.

Kind regards
Lrac

Peter_1
28-11-2006, 11:26 PM
I have one (SDT, Belgium product)since +/ 20 years and I disagree with certain things you Lrac.
They can be used perfect in a noisy environment. They only pick-up the ultrason frequencies.
If it's too noisy, then you allways have your headphone.
Most leaks produce an ultrason noise, so you can even test them while pulling a vacuum.
But..you find the leaks much faster with an electronic sniffer.

As Brian said, I bought mine after seeing it on a fair where they demonstrated it on the seal of a car door.
So they're very good to test the seals on doors of refrigerated rooms. But for that, you need the ultrasonic transmitter.

It's very often used here in Belgium for the 5-yearly certification test of underground fuel tanks.

I also have the pick-uop piece to check bearings and flow inside tubes, valves, pumps.

The device only converts unhearable sounds to a hearable level. That's all.

Dan
03-12-2006, 02:26 AM
An ultrasonic leak detector is an important tool for leak detection. I have a cheaper one that has found leaks that could otherwise not have been pinpointed.

Here is a typical scenario: You know you have a leak in a large area that you narrow down to a cubic meter or so. But the electronic and soap bubbles fail you. Turn everything off, and put the headphones on, and you will hear a roaring leak immediately. It could be, as it was last time I found one, a small crack on the bottom of the cap tube for an oil failure control. Impossible to find with bubbles, until you know it is there, and then you put your mirror under it and see the soap spray onto the mirror.

Ultrasonics are also useful for finding large leaks in overhead piping and outdoor units where wind makes electronics less useful. Much of the ambient noise is filtered out, but the more silent you can make the equipment, the more obvious the leak becomes. With my ultrasonic, you can stand 10 feet away and home in on the sound of my finger and thumb rubbing together.

steveg
09-12-2006, 11:13 PM
hello
i have used the agramkow saratronic leak detector that uses protec 5 and a sniffer. big bulky and expensive are the main problem. the best unit i have used for manufacturing applications is the inficon unit that can detect any gas, they cost 15k each but you get what you pay for as these will sense down to 1 gram per year

MechAcc
30-12-2006, 06:05 PM
Face it there are excellent ultrasonics and there are poor ultrasonics. Shop wisely before you buy

Latte
30-12-2006, 07:38 PM
Hi All,.

Until a couple of weeks ago i would have said an ultrasonic leak detector was an expensive waste of money. However, i went on a True course a couple of weeks ago and had a play with one and was very impressed. If you have a small leak they are fantastic, especially for them had to trace leaks on evaperators where you may think the evaps gone but its actually a joint.

Something i need to look into at some point.

I am also in the market for a megger/RCD tester. Not planning to use it much so not looking at top end stuff, just something that does the job when needed. Plan to go round city electrical/WF and Newey and Eyres in the new year, any suggestions ?

Regards

Fatboy

peterburnett
30-12-2006, 09:08 PM
I bought one but still prefer OFN

LRAC
31-12-2006, 10:09 AM
Hi All,.

i went on a True course a couple of weeks ago and had a play with one and was very impressed. Fatboy

Hi fatboy was the training at P&S williams, went on one my self kit didn't impress me that much but made a nice day out.

Lrac

MechAcc
04-01-2007, 12:49 PM
Hi All,.

Until a couple of weeks ago i would have said an ultrasonic leak detector was an expensive waste of money. However, i went on a True course a couple of weeks ago and had a play with one and was very impressed. If you have a small leak they are fantastic, especially for them had to trace leaks on evaperators where you may think the evaps gone but its actually a joint.

Something i need to look into at some point.

I am also in the market for a megger/RCD tester. Not planning to use it much so not looking at top end stuff, just something that does the job when needed. Plan to go round city electrical/WF and Newey and Eyres in the new year, any suggestions ?

Regards

Fatboy



Unfamiliar with your term RCD. Fluke has a new multimeter out with megger functions can also measure capacitance.

jcook1982
09-02-2010, 06:28 PM
I've found electronic leak detectors to be superior over the Ultrasonic.. Maybe in a perfect environment they work. I purchased one and regret it.. The only ambient noise a field tech is really going to experience is other refrigeration/ ac units in operation. Electronic Leak Detectors are much better.

oldesky
09-02-2010, 11:40 PM
We had a small RAC that was leaking a few years ago. We brought it back to the workshop for testing as noone could locate the leak on site. We tried bubble leak, ultrasonic detector,electronic leak detector and dye. The dye was showing leaks on 4 evap U bend joints but none of the other detectors picked up the leaks. I have found the dye to work quite well on small self contained systems. The Ultrasonic detectors have probably improved since but I have found a good quality electronic detector to be the best overall. Has anyone tried an electronic CO2 detector? We are looking at trialing this in the factory for testing new units.

Emmett
10-02-2010, 05:34 PM
I have used ultrasonic detectors with mixed result's. With the unit I have used it was impossible o filter out the background noise sufficiently to make the device usable, however when everything is shut down it works well. I only use it as a last resort, electronic and soap bubbles is the way to go.

Fri3Oil System
27-04-2010, 03:47 PM
In Spain people are really satisfied with Ultrasonic leak locators. They're actually quite accurate for finding small leaks. But there are other applications, like checking bearings, compressors, leaky valves... etc.

Aik
06-05-2010, 11:30 AM
If i remember correctly they are more tuned to detecting sounds at 40Khz if your gas leak is on this frequency ok, but if not your stuufed.

Lrac
The gas leak is on freqency of 36 - 40 kHz

Fri3Oil System
06-05-2010, 11:34 AM
The ultrasonic leak locators are normally callibrated or tuned on 40Khz, and leaks are between 38 to 42 more or less.
You can also check bearings malfunctions. On some devices, you can change the frecuency to 25Khz.

hvacrmedic
17-05-2010, 03:13 AM
I'm almost regretting this before i start! has anyone seen,used, touched, played with any ultra sonic leak detection gear, we are thinking of investing in the equipment but i dont want to commit funds on the say so of a hot shot salesman.

A suited gent who works for a mighty intrenational fridge company tells me they are the best thing ever but due to a "technical problem" he was unable to prove it. Any views:confused:

I have the Amprobe ultrasonic kit. I have no complaints with it whatsoever. I'm very impressed with it actually. Some patience is required when learning to properly use the instrument though. For evap coils, spray the surfaces with water first. The bubbling noise is unmistakable, and will allow detection of leaks down to hundredths of an ounce per year (formicary corrosion).

There are times when electrical interference, or even insect interference, is too great to use it, but that isn't a good reason to condemn the instrument. No method is 100%. Pressure testing only tells you whether there is leak, but doesn't pinpoint the leak for you. Electronic sniffers don't work when there's a breeze, and cannot always pinpoint the source even though it detects the leak. Bubble solution can only be used to check exposed portions of the system, and can blow off of the leak. UV dye is actually the most consistent method in my experience, but requires a return visit, and possible callback due to excessive refrigerant loss before the return visit.

It's good to have an assortment of methods available, and FWIW the ultrasonic is my favorite instrument/method of the bunch. It's the first thing that I pick up.

worldb
30-08-2010, 04:26 PM
I use the UL101 Ultrasonic Leak detector. The difference between this and others I've seen is astounding. No background noise and you don't have to adjust the sensitivity. I understand NASA uses it for vacuum leaks in space. The only problem is laminar flow leaks (no ultrasound), in which case a sniffer must be used, but the UL101 is much easier and more reliable in noisy environments, wind, etc.